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lakatu · 06-24-2004, 03:09 PM

Thanks st-anger for the information. So it sound like the limiting factor that prevents the CGT from utilizing the 33% lower power/weight ratio over the GT3 RS to post an even lower time is the grip available from the tires. You can’t be faster than your weakest link

. Makes sense since all of the acceleration/deceleration and lateral forces have to be transmitted through the tires.

It looks to me like the decrease in power/weight ratios over the years is the main factor decreasing NS times for the 911 from 9.22 (1987 911) to today’s 8.20. Do you agree and how much of a difference do you think the suspension improvements over the years make?

Porsche, for some reason not clear to me, has always tended to have smaller wheels than would fit under the car

. For example, the 911 Club Sport which was aimed at track day enthusiast had 6” front and 7” back. While you could order a 7”/8” sport package on the base 911. Current 996 runs 8”/10” and I’m sure that these wider wheels along with improvement in tire technology has contributed to the big improvements in lateral acceleration.

I have wondered how much faster on the NS an older 911 with new technology tires and wider tire/rims would be

. This is especially true for the 930 series that can handle 9”/12” verses the OEM 7”/9”.

There must be some reason for the smaller tire preference by Porsche. There are a few trade offs that I am aware of like potentially higher unsprung weight, increased rolling resistance and higher drag coefficients. But since the trend has been to wider wheels and tires over the years I wonder why Porsche didn’t do it earlier. Maybe there wasn’t enough money to develop wider Fuchs back then.

Any thoughts or comments on these issues

06-24-2004, 03:09 PM	#10
lakatu Regular User Join Date: Oct 2003 Location: United States Posts: 408	Thanks st-anger for the information. So it sound like the limiting factor that prevents the CGT from utilizing the 33% lower power/weight ratio over the GT3 RS to post an even lower time is the grip available from the tires. You can’t be faster than your weakest link . Makes sense since all of the acceleration/deceleration and lateral forces have to be transmitted through the tires. It looks to me like the decrease in power/weight ratios over the years is the main factor decreasing NS times for the 911 from 9.22 (1987 911) to today’s 8.20. Do you agree and how much of a difference do you think the suspension improvements over the years make? Porsche, for some reason not clear to me, has always tended to have smaller wheels than would fit under the car . For example, the 911 Club Sport which was aimed at track day enthusiast had 6” front and 7” back. While you could order a 7”/8” sport package on the base 911. Current 996 runs 8”/10” and I’m sure that these wider wheels along with improvement in tire technology has contributed to the big improvements in lateral acceleration. I have wondered how much faster on the NS an older 911 with new technology tires and wider tire/rims would be . This is especially true for the 930 series that can handle 9”/12” verses the OEM 7”/9”. There must be some reason for the smaller tire preference by Porsche. There are a few trade offs that I am aware of like potentially higher unsprung weight, increased rolling resistance and higher drag coefficients. But since the trend has been to wider wheels and tires over the years I wonder why Porsche didn’t do it earlier. Maybe there wasn’t enough money to develop wider Fuchs back then. Any thoughts or comments on these issues __________________ Porsche, there is no substitute. Well except RS Tuning and Manthey.